building autocross festiva

[blake4591]

Hi everyone,
I've been lurking about for a few months trying to plan out my Festiva build and finally have enough time and money to get it started. I'm mostly going for a competitive autocross car that is still street-able enough to drive to work so for now I'm thinking something like this

Brakes (100):
Aspire sway w/ EGT master cylinder

Wheels and tires (300 to 400):
cheapest 15" rims (preferably aluminum) and 195/50 or 205/50 tires depending on budget

Suspension:

Front (150):
Asprie sway bar, complete Rio struts, mounts and springs (with some coils cut).
I would like to run adjustable mounts if there are any that can be easily modified to work.
I remember seeing a thread about putting ploy bushings in the LCA may also do that if it helps alot.

Rear (150):
Rio springs (cut to be level with front) on either Aspire Monroes or struts form a cavalier or accord if they well work with the springs and clear the tires.
Aspire beam

Also thinking possibly strut tower brace and threaded rod mod (if possible with the Aspire beam?) to help with rear stiffness. Its my understanding that on front wheel drive cars it is best the make the rear as stiff as possible (without causing yourself to spin out all the time) to help with traction while exiting corners.

Engine (rest of money I have):
would like to do a B8-ME if funds permit. if not then I will do the typical simple stuff to try and get a few extra horses out of the 1.3.

A friend suggested I just leave the engine stock and buy coilovers, is this a good idea?

Total I'm looking to spend between $800 to $1000 on all of this.

Does this seem like everything will work? Anyone have experience with autocrossing a setup at all similar? Any advice for me before I start building this?

Any and all help is appreciated.

[IdealSociety]

a b6 alone might work well in autox since it'll help keep weight down in the front where your fwd is already well loaded.

a 20hp increase and a couple hours to swap between them makes it a worthwhile job.

Otherwise the aspire rear already has the rod inside the beam, make sure however that you make something to box up the top end of the strut towers in the rear for sure. the festiva was built with alot of chassis flex so anywhere you can seam weld is a big help as well as those tower braces will make a huge difference alone.

Dont go too stiff on the rear end, but make it quite firm. If you make the rear too stiff, all the energy that previously went into body roll will transfer straight to the tires and you'll need wider rears to keep the back from possibly losing traction in a hard corner.

Dont use 15" wheels. Do some research on unsprung weight and you'll see why. if you can find the widest 13" steelies you can fit under the fenders (or cut/flare your fenders and go even wider) and the best rated set of tires allowed, ignore speed ratings, stick with a good soft compound since you'll be throwing it into corners pretty hard.

Diamond racing wheels are relatively cheap and are very light. I wouldnt use them as daily wheels here in MN since we have potholes bigger than most east coast states but they are good for track use.

Now, i've never done autoX so if anyone with better experience on the subject knows differently feel free to speak up. Im making all my judgements on my "spirited" everyday driving style

[blkfordsedan]

Most of the autox cars I've seen that are fwd actually lift the inside rear wheel during hard cornering. The theory is that it transfers the weight to the front wheels to pull you out of the corner. To go along with this, the front wheels need to be able to articulate independently in order to keep them both planted for traction. Increasing the weight to the front will also tend to increase oversteer. So the key is to have just a stiff enough front sway bar to keep the steering neutral. Too stiff, and you will loose traction and understeer. Too weak, and you'll get oversteer. At least that's what I have gathered from the chassis tuning books I've read. I would start with the stock Festy front sway bar with Urethane bushings and see how it works.

[mikeycar500]

I ran my first year I took first place and rookie of the year. The b3 was stock not even a airfilter upgrade. I did a aspire swap with skunk2 coilovers. Stock swaybar cause it was handling so good i did not want to mess with it. I ran a set of 194 45 r14 (hard to find now) but this year I have aero race rims (13x8). Plus the smaller the tire the faster u can accelerate and it keeps your car down low where u want it. Hope this helps ya out

[blake4591]

Well in the past couple days I have been finalizing my planning before I go to pull some parts this weekend.

Found that Rio springs wont work in the rear so I'm now thinking I'll just use Aspire fronts.

I was also checking out the SCCA classes and am thinking that the 1.3 is most likely going to stay as most classes don't allow engine swaps. This gives me a little more money to spend so...

Should I just buy a cheap (RSK or raceland) golf mk3 coil-over kit? or is it going to be to stiff?
I live in Michigan so the roads are pretty rough are the 350/250 spring rates livable for a daily driver?

As far as the wheels go i was mostly thinking 15s to keep the sidewalls small and get to affordable easy to find performance tires. I appreciate the advice and I know that unsprung weight is bad for handling and heavier tires hurt acceleration but, from my experience autocrossing wide sticky tires are the key to getting around the corners as fast as possible and wide sticky tires are cheaper and more available for 14 and 15s Unless you know where i can get cheap wide tires for 13s cause if you do I'll buy them

Thanks for the advice so far and once I start turning wrenches I'll start a build thread.

[bhazard]

Go with the coilover kit, dont bother with anything remotely stock, especially FMS springs, aspire or rio, theyre still maybe 125lb tops.

Go with the lightest wheel/tire combo possible.

Swap in an early B6 longblock. Looks completely stock.

[russian]

With 205/50 tires you should probably avoid 15x5.5 rims

[bhazard]

A 50 series tire is still gonna have a lot of sidewall too.

[Safety Guy]

I haven't done auto-x either, but here are some thoughts:

If you do go 15" wheels, check out the five spoke Miata 15 X 6" wheels. You may be able to get a deal on some used ones. Instead of 195/50s, go with 195/45-15s since there is a very wide variety of choices in that size. These will be about 10mm taller than stock so they won't be too tall. Run Aspire spec rear struts for better tire clearance.

The 15 X 6" Miata wheels weigh 13.1 pounds each, and with tires that could weigh as little as 17 pounds you should be around 30 pounds at each wheel. These are not as light as you would go with the 14 X 6" Miata solid or hollow spokes with Toyo Proxes in 195/45-14, but the Toyos are so darn expensive and harder to find nowadays. In comparison, the 195/45-15s are plentiful and run from around $65 or so to about $85 each for the same Proxes version! Check out Tires-easy and look around.

If you really want lightweight wheels, see if you can get Honda VXs (13 X 5") or HXs (14 X 5.5"), which are 9 pounds and 11 pounds respectively. I just weighed a VX wheel and one of my 175/60-13 Falkens (14 or 15 pounds) the other day and the combo is 23 to 24 pounds! Not as much rubber on the road, but very light, will accelerate quickly, and should provide pretty good grip. If you find some 175/50-13 tires (yes, they're out there), that may be an even better choice.

Check out Craigslist for used Miata or Honda wheels.

I'm not saying these are the "best," but they should be do-able price wise if you look for them and they will probably get you off to a good autocross start.

I think your main challenge here is to get your car auto-x competitive while maintaining relatively comfortable street manners. With coil overs you may at least try the 350/250 route, and if they're too stiff you could swap in some lighter springs.

Good luck!

Karl

[Safety Guy]

Here's two examples of tires from Tire Rack, which had only one selection of 195/45-15 (but compare that with NO choices of 195/45-14):

http://www.tirerack.com/tires/tires.jsp?tireMake=Yokohama&tireModel=S.drive&partnum=945WR5S&vehicleSearch=false&fromCompare1=yes

So put the above 195/45-15 s.drive (18 pounds) on a 15 X 6" Miata five spoke (13.1 pounds) and you see you will have about 31 pounds. (One good thing about Tirerack is that they list specs including weights and the wheel width ranges for best results and safety.)

Compare that with the 185/55-14 s.drive (click on the link in "specs") and you see that size weighs in at 17 pounds each. Add that weight to a commonly sold set of Miata "Daisies" (14 X 5.5" and 12.3 pounds) and you have a total weight of under 30 pounds per corner.

Now consider "cost effectiveness." What are you willing to pay? You could get new aftermarket wheels for a whole buncha money, or used Miata wheels at whatever you can find, depending on how lucky and patient you are. I've bought a set of Daisies for $80. I also got a set of solid spokes (14 X 6" at 11.5 pounds) for $60 and barely drove three blocks from you house to pick them up!

Then compare the price of the 15" s.drives vs. the 14" ones. Then again, go to Tires-easy, which has a large selection of the 15s and only one 14", the Falkens. Use a blank sheet of paper and write down the potential combos and see what you can afford and like. Etc. Here is the link to Tires-easy, for your convenience:

http://www.tires-easy.com/start.html

Can you tell I've done some thinking and comparing of my own lately?

I'd guess you could get the used Miata 15" wheels for around $200 to $280 or so if you keep looking. Same with either of the two Honda sizes mentioned. I got my VXs for $85 just a couple months ago!

New aftermarket wheels could weigh as little as 10 pounds for 15 X 6.5", but you'll pay over $400 for a set. Is it worth it? Only you can say. One thing I'll add is that brand new "tuner" wheels will attract a lot more attention from thieves than your used Miata wheels.

Invest in some good wheel locks while you're at it, even with the used Miata or Honda wheels. Oh, one more excellent resource:

http://www.miata.net/faq/wheel_weights.html

IMO, used Miata wheels in several different sizes are some of the best deals you can find for an Aspire swapped Festiva. Direct fit, good offsets which should work pretty well, and no question about centerbore sizing, since all Miata wheels will fit like they were made for your Aspire hubs!

I'll shut up now.

Karl

[blake4591]

I went to the junkyard today. They told me that they had two Aspires in the yard turns out they have one that was missing the drive-train and front suspension so no luck there but I did pick up some stuff for other projects. I have two other junkyards to go to tomorrow hopefully one will have an unpicked Aspire.

when I got home though I managed to pick up a set of 14s off a Miata with Falken Azenis RT215 195/60R14 for $200 so the wheel tire combo is set for now. I appreciate all the advice on the topic but this deal was just too good to pass up Once they were out I'll probably step down to a 195/50 or something in the 185.

Also spent some time at the bar with my friend that competes in national level auto-crosses. He said that the coil-overs should be legal in stock prepared (since the coils are over the struts on all four corners form the factory) and that he thought the Festiva could be competitive in the class once set up properly (I let him drive it at an its first autocross so I'm going to say he has a pretty good idea of what hes talking about).

[blake4591]

well I'm slightly annoyed right now because after a whole weekend of trying to find an Aspire to pull parts off of all I ended up with was an Escort GT master cylinder. I'm considering just trying to buy an Aspire pull what I need and then scarp it. I never thought that it would be hard to find one with all the parts still on it in detroit turns out I was wrong.

[rollertoaster]

You may want to combine the egt master cyl with an aspire booster. The stock festy booster made the pedal super hard to push on mine, the aspire booster made it stiff but manageable.


Sent from my iPhone using Tapatalk

[Advancedynamix]

Miata booster is super low profile and its a dual diaphragm unit. It works great! I use the 7/8" Miata m/c as well.

[Safety Guy]

Charlie wrote:

"Miata booster is super low profile and its a dual diaphragm unit. It works great! I use the 7/8" Miata m/c as well."

Any particular year? I looked up '92 Miata parts at Rockauto and the pics show the non-ABS unit as having two ports (one top/one right) at the nose and one port that takes a brass colored thingy on the middle left. I have no idea what that is.

If you could post pics, Charlie, it would be nice.

(I just tried to attach a pic of the Miata brake booster from RA but it was "invalid.")

I will say the Miata booster does indeed look "low profile." I wonder if it weighs less too?

Karl